Fair Value - Schedule of Difference between the Aggregate Fair Value and the Aggregate Remaining Principal Balance (Detail) (Residential Loans Held for Sale [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Residential Loans Held for Sale [Member]
Fair Value, Estimate Not Practicable, Financial Statement Captions [Line Items]
Aggregate Fair Value	$ 7,918	$ 9,911
Difference	311	255
Contractual Principal	$ 7,607	$ 9,656